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111.
De Giglio E Cometa S Cioffi N Torsi L Sabbatini L 《Analytical and bioanalytical chemistry》2007,389(7-8):2055-2063
A polyacrylic acid film was synthesized on titanium substrates from aqueous solutions via an electroreductive process for
the first time. This work was done in order to develop a versatile coating for titanium-based orthopaedic implants that acts
as both an effective bioactive surface and an effective anti-corrosion barrier. The chemical structure of the PAA coating
was investigated by X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) was employed to evaluate the
effect of annealing treatment on the morphology of the coatings in terms of their uniformity and porosity. Inductively coupled
plasma mass spectrometry was used to measure ion concentrations in ion release tests performed on Ti-6Al-4V sheets modified
with PAA coatings (annealed and unannealed). Results indicate that the annealing process produces coatings that possess considerable
anti-corrosion performance. Moreover, the availability and the reactivity of the surface carboxylic groups were exploited
in order to graft biological molecules onto the PAA-modified titanium implants. The feasibility of the grafting reaction was
tested using a single aminoacid residue. A fluorinated aminoacid was selected, and the grafting reaction was monitored both
by XPS, using fluorine as a marker element, and via quartz crystal microbalance (QCM) measurements. The success of the grafting
reaction opens the door to the synthesis of a wide variety of PAA-based coatings that are functionalized with selected bioactive
molecules and promote positive reactions with the biological system interfacing the implant while considerably reducing ion
release into surrounding tissues.
Figure Vanadium release from bare Ti-6Al-4V sheets compared with the release from sheets coated with annealed and unannealed electrosynthesised
PAA
Dedicated to Professor P.G. Zambonin on the occasion of his 72nd birthday. 相似文献
112.
复杂阴极保护体系三维有限元建模研究 总被引:1,自引:0,他引:1
滨海电厂常以天然海水作冷却水,其碳钢水室和钛管凝汽器在实施阴极保护过程中,要求钢电位应低于-0.85V(vs.SCE),电位过正则碳钢保护不足,而钛的电位则须高于-0.75V(vs.SCE),电位过负则易使钛管发生氢脆损伤.研究牺牲阳极阴极保护,需先得出两种金属在阴极保护过程中的电位分布.本文在设计室建立碳钢水室钛管模型,根据该实验体系阴极保护过程的(稳态极化和恒电流极化)测定获得两种金属有效的边界条件,用有限元(FEM)计算在一个牺牲阳极阴极保护状态得到三维电位分布.计算结果和测量结果基本一致,为优化阴极保护设计提供了理论依据. 相似文献
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116.
Wen Xing Chaoling Wen Deguo Wang Hui Shao Chunhong Liu Chunling He Opeyemi Joshua Olatunji 《Molecules (Basel, Switzerland)》2022,27(7)
Doxorubicin (DXB) is one of the most commonly used anticancer agents for treating solid and hematological malignancies; however, DXB-induced cardiorenal toxicity presents a limiting factor to its clinical usefulness in cancer patients. Costunolide (COST) is a naturally occurring sesquiterpene lactone with excellent anti-inflammatory, antioxidant and antiapoptotic properties. This study evaluated the effect of COST on DXB-induced cardiorenal toxicity in rats. Rats were orally treated with COST for 4 weeks and received weekly 5 mg/kg doses of DXB for three weeks. Cardiorenal biochemical biomarkers, lipid profile, oxidative stress, inflammatory cytokines, histological and immunohistochemical analyses were evaluated. DXB-treated rats displayed significantly increased levels of lipid profiles, markers of cardiorenal dysfunction (aspartate aminotransferase, creatine kinase, lactate dehydrogenase, troponin T, blood urea nitrogen, uric acid and creatinine). In addition, DXB markedly upregulated cardiorenal malondialdehyde, tumor necrosis factor-α, interleukin-1β, interleukin-6 levels and decreased glutathione, superoxide dismutase and catalase activities. COST treatment significantly attenuated the aforementioned alterations induced by DXB. Furthermore, histopathological and immunohistochemical analyses revealed that COST ameliorated the histopathological features and reduced p53 and myeloperoxidase expression in the treated rats. These results suggest that COST exhibits cardiorenal protective effects against DXB-induced injury presumably via suppression of oxidative stress, inflammation and apoptosis. 相似文献
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本文结合阻燃科学技术,对阻燃剂及其应用、阻燃剂处理方法及加工技术、防火涂料、防火板和防火液的基本原理与加工技术中所蕴含和运用的化学知识和原理进行系统归纳和整理,以期加强消防专业化学教学的针对性和实用性,激发消防专业学生学习化学的兴趣,同时为其他化学教学提供实践教学案例。 相似文献
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Shuai Huang Huanxi Zheng Jiyu Liu Jinlong Song Faze Chen Xiaolong Yang 《Journal of Dispersion Science and Technology》2017,38(4):566-569
Selective fabrication of superhydrophilic (S-philic) region on a superhydrophobic (S-phobic) surface requires complex technology and high cost, which has limited applications of extreme wettability patterns. In this paper, a twice-chemical-etching approach without special modification is used to prepare the extreme wettability patterns. Superhydrophobicity and superhydrophilicity can be successfully achieved after twice chemical etching for 20 seconds. The obtained patterns can maintain their extreme wettability for at least 30 days. Functional platforms with single-S-philic and multi-S-philic regions are fabricated to manipulate water and various organic liquids with water-film protection in an air environment. 相似文献